   (testing "Using completable future as body."
     (letfn [(handler [ctx]
               (http/ok (p/promise (fn [resolve reject]
-                                    (async/<!! (async/timeout 1000))
+                                    (a/<!! (a/timeout 1000))
                                     (resolve "hello world")))))]
       (with-server {:handler handler}
         (let [response (client/get base-url)]

            [clojure.test :refer :all]
            [clojure.java.io :as io]
            [clojure.pprint :refer [pprint]]
            [clojure.core.async :as async]
            [clj-http.client :as client]
            [promesa.core :as p]
            [catacumba.stream :as stream]

  (testing "Using completable future as response."
    (letfn [(handler [ctx]
              (p/promise (fn [resolve reject]
                           (a/<!! (a/timeout 1000))
                           (resolve (http/ok "hello world")))))]
      (with-server {:handler handler}
        (let [response (client/get base-url)]
